Issue #2815077 by drpal, mradcliffe, effulgentsia, mpdonadio, nod_, droplet, alexpott, nedjo, tizzo, David_Rothstein, pfrenssen: Adopt airbnb javascript style guide v13 as new baseline javascript coding standards for Drupal 8 core and contrib

.eslintignore

@@ -1,5 +1,4 @@
-core/assets/vendor/**/*
+core/**/*
-core/modules/locale/tests/locale_test.js
 vendor/**/*
 sites/**/files/**/*
 libraries/**/*

core/.eslintignore

@@ -2,3 +2,5 @@ assets/vendor/**/*
 modules/locale/tests/locale_test.js
 node_modules/**/*
 **/js_test_files/**/*
+*.js
+!*.es6.js

core/.eslintrc.json

@@ -1,5 +1,6 @@
 {
-  "extends": "eslint:recommended",
+  "extends": "eslint-config-airbnb",
+  "root": true,
   "env": {
     "browser": true,
     "es6": true,
@@ -18,80 +19,23 @@
     "CKEDITOR": true
   },
   "rules": {
-    // Errors.
+    "consistent-return": [0],
-    "array-bracket-spacing": [2, "never"],
+    "no-underscore-dangle": [0],
-    "block-scoped-var": 2,
-    "brace-style": [2, "stroustrup", {"allowSingleLine": true}],
-    "comma-dangle": [2, "never"],
-    "comma-spacing": 2,
-    "comma-style": [2, "last"],
-    "computed-property-spacing": [2, "never"],
-    "curly": [2, "all"],
-    "eol-last": 2,
-    "eqeqeq": [2, "smart"],
-    "guard-for-in": 2,
-    "indent": [2, 2, {"SwitchCase": 1}],
-    "key-spacing": [2, {"beforeColon": false, "afterColon": true}],
-    "keyword-spacing": [2, {"before": true, "after": true}],
-    "linebreak-style": [2, "unix"],
-    "lines-around-comment": [2, {"beforeBlockComment": true, "afterBlockComment": false}],
-    "new-parens": 2,
-    "no-array-constructor": 2,
-    "no-caller": 2,
-    "no-catch-shadow": 2,
-    "no-eval": 2,
-    "no-extend-native": 2,
-    "no-extra-bind": 2,
-    "no-extra-parens": [2, "functions"],
-    "no-implied-eval": 2,
-    "no-iterator": 2,
-    "no-label-var": 2,
-    "no-labels": 2,
-    "no-lone-blocks": 2,
-    "no-loop-func": 2,
-    "no-multi-spaces": 2,
-    "no-multi-str": 2,
-    "no-native-reassign": 2,
-    "no-nested-ternary": 2,
-    "no-new-func": 2,
-    "no-new-object": 2,
-    "no-new-wrappers": 2,
-    "no-octal-escape": 2,
-    "no-process-exit": 2,
-    "no-proto": 2,
-    "no-return-assign": 2,
-    "no-script-url": 2,
-    "no-sequences": 2,
-    "no-shadow-restricted-names": 2,
-    "no-spaced-func": 2,
-    "no-trailing-spaces": 2,
-    "no-undef-init": 2,
-    "no-undefined": 2,
-    "no-unused-expressions": 2,
-    "no-unused-vars": [2, {"vars": "all", "args": "none"}],
-    "no-with": 2,
-    "object-curly-spacing": [2, "never"],
-    "one-var": [2, "never"],
-    "quote-props": [2, "consistent-as-needed"],
-    "quotes": [2, "single", "avoid-escape"],
-    "semi": [2, "always"],
-    "semi-spacing": [2, {"before": false, "after": true}],
-    "space-before-blocks": [2, "always"],
-    "space-before-function-paren": [2, {"anonymous": "always", "named": "never"}],
-    "space-in-parens": [2, "never"],
-    "space-infix-ops": 2,
-    "space-unary-ops": [2, { "words": true, "nonwords": false }],
-    "spaced-comment": [2, "always"],
-    "strict": [2, "function"],
-    "yoda": [2, "never"],
-    // Warnings.
     "max-nested-callbacks": [1, 3],
+    "no-mutable-exports": [1],
+    "no-plusplus": [1, {
+      "allowForLoopAfterthoughts": true
+    }],
+    "no-param-reassign": [0],
+    "no-prototype-builtins": [0],
     "valid-jsdoc": [1, {
       "prefer": {
         "returns": "return",
         "property": "prop"
       },
       "requireReturn": false
-    }]
+    }],
+    "brace-style": ["error", "stroustrup"],
+    "no-unused-vars": [1]
   }
 }

core/.eslintrc.legacy.json

@@ -0,0 +1,94 @@
+{
+  "extends": "eslint:recommended",
+  "root": true,
+  "env": {
+    "browser": true
+  },
+  "globals": {
+    "Drupal": true,
+    "drupalSettings": true,
+    "drupalTranslations": true,
+    "domready": true,
+    "jQuery": true,
+    "_": true,
+    "matchMedia": true,
+    "Backbone": true,
+    "Modernizr": true,
+    "CKEDITOR": true
+  },
+  "rules": {
+    "array-bracket-spacing": [2, "never"],
+    "block-scoped-var": 2,
+    "brace-style": [2, "stroustrup", {"allowSingleLine": true}],
+    "comma-dangle": [2, "never"],
+    "comma-spacing": 2,
+    "comma-style": [2, "last"],
+    "computed-property-spacing": [2, "never"],
+    "curly": [2, "all"],
+    "eol-last": 2,
+    "eqeqeq": [2, "smart"],
+    "guard-for-in": 2,
+    "indent": [2, 2, {"SwitchCase": 1}],
+    "key-spacing": [2, {"beforeColon": false, "afterColon": true}],
+    "keyword-spacing": [2, {"before": true, "after": true}],
+    "linebreak-style": [2, "unix"],
+    "lines-around-comment": [2, {"beforeBlockComment": true, "afterBlockComment": false}],
+    "new-parens": 2,
+    "no-array-constructor": 2,
+    "no-caller": 2,
+    "no-catch-shadow": 2,
+    "no-eval": 2,
+    "no-extend-native": 2,
+    "no-extra-bind": 2,
+    "no-extra-parens": [2, "functions"],
+    "no-implied-eval": 2,
+    "no-iterator": 2,
+    "no-label-var": 2,
+    "no-labels": 2,
+    "no-lone-blocks": 2,
+    "no-loop-func": 2,
+    "no-multi-spaces": 2,
+    "no-multi-str": 2,
+    "no-native-reassign": 2,
+    "no-nested-ternary": 2,
+    "no-new-func": 2,
+    "no-new-object": 2,
+    "no-new-wrappers": 2,
+    "no-octal-escape": 2,
+    "no-process-exit": 2,
+    "no-proto": 2,
+    "no-return-assign": 2,
+    "no-script-url": 2,
+    "no-sequences": 2,
+    "no-shadow-restricted-names": 2,
+    "no-spaced-func": 2,
+    "no-trailing-spaces": 2,
+    "no-undef-init": 2,
+    "no-undefined": 2,
+    "no-unused-expressions": 2,
+    "no-unused-vars": [2, {"vars": "all", "args": "none"}],
+    "no-with": 2,
+    "object-curly-spacing": [2, "never"],
+    "one-var": [2, "never"],
+    "quote-props": [2, "consistent-as-needed"],
+    "quotes": [2, "single", "avoid-escape"],
+    "semi": [2, "always"],
+    "semi-spacing": [2, {"before": false, "after": true}],
+    "space-before-blocks": [2, "always"],
+    "space-before-function-paren": [2, {"anonymous": "always", "named": "never"}],
+    "space-in-parens": [2, "never"],
+    "space-infix-ops": 2,
+    "space-unary-ops": [2, { "words": true, "nonwords": false }],
+    "spaced-comment": [2, "always"],
+    "strict": [2, "function"],
+    "yoda": [2, "never"],
+    "max-nested-callbacks": [1, 3],
+    "valid-jsdoc": [1, {
+      "prefer": {
+        "returns": "return",
+        "property": "prop"
+      },
+      "requireReturn": false
+    }]
+  }
+}

core/package.json

@@ -6,14 +6,18 @@
   "scripts": {
     "build:js": "node ./scripts/js/babel-es6-build.js",
     "watch:js": "node ./scripts/js/babel-es6-watch.js",
-    "lint:js": "eslint . || exit 0"
+    "lint:core-js": "node ./node_modules/eslint/bin/eslint.js --ext=.es6.js . --fix || exit 0"
   },
   "devDependencies": {
-    "babel-core": "6.17.0",
+    "babel-core": "6.24.1",
     "babel-preset-es2015": "6.16.0",
-    "chokidar": "1.6.0",
+    "chokidar": "1.6.1",
-    "eslint": "3.8.1",
+    "eslint": "3.19.0",
-    "glob": "^7.1.1"
+    "eslint-config-airbnb": "14.1.0",
+    "eslint-plugin-import": "2.2.0",
+    "eslint-plugin-jsx-a11y": "4.0.0",
+    "eslint-plugin-react": "6.10.3",
+    "glob": "7.1.1"
   },
   "babel": {
     "presets": [